
\begin{abstract}
%Current 3GPP standards on LTE RAN sharing is limited
\iffalse
With the continued exponential growth of mobile traffic and the rise of
diverse applications, the bulky LTE procedures in current radio access
networks (RAN) of cellular operators face mounting challenges. 
Current RAN suffers from insufficient radio resource coordination, inefficient
infrastructure utilization, inflexible protocol upgrade.
We present the high level of PRAN, which centralizes base stations' L1/L2 processing into a
cluster of commodity servers. PRAN uses a flexible data path model to support
new protocols; multiple base stations' L1/L2 processing is scheduled on
servers with performance guarantee; and a RAN scheduler coordinate radio
resources between operators and base stations.
Our evaluation shows the feasibility of fast data path control and efficiency 
of resource pooling (a factor of 30 reduction on resources). 
\fi
With the continued exponential growth of mobile traffic and the rise of
diverse applications, the current LTE radio access network (RAN) architecture of
cellular operators face mounting challenges. Current RAN suffers from
insufficient radio resource coordination, inefficient infrastructure
utilization, and inflexible data paths. We present the high level design of PRAN,
which centralizes base stations' L1/L2 processing into a cluster of commodity
servers. PRAN uses a flexible data path model to support 
new protocols; multiple base stations' L1/L2 processing tasks are scheduled on
servers with performance guarantees; and a RAN scheduler coordinates the
allocation of shared radio resources between operators and base stations. Our
evaluation shows the feasibility of fast data path control and efficiency of
resource pooling (a potential for a 30$\times$ reduction on resources).  
\end{abstract}
